Skin tests (extract based) | Molecular-based sIgE tests (component based) |
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Available only where equipment, reagents and trained staff are on hand. | Available only in laboratories with high-end machinery where specific reactives and trained staff are on hand. |
Moderately costly. | High cost. |
Minor discomfort for scratching, itch if positive. | Minor pain. Venesection may be painful or anxiety-provoking (particularly in children), |
Requires patient cooperation. Performance in small children may be limited. | Little patient effort or cooperation required. |
Slight risk of systemic allergic reaction (more so in some special situations). A convincing recent history of anaphylaxis represents a contra-indication. | No risk to patient; may be first line with certain high-risk allergens. |
Require areas of normal skin for testing. | Can be done regardless of extensive skin disease. |
Must stop antihistamines and some other drugs several days before test. | Can be done regardless of taken medications. |
Methodology and result quality variable, standardization not always possible. No formal quality control at the current time. | Laboratory test subject to strict quality control, reagent availability and technique standardization. |
Results in 30 min | Results may take days/weeks. |
Results are visible and compelling to patients; may have value in ensuring compliance with allergen avoidance measures. | Results are not directly meaningful to patients. |
Can extemporaneously prepare allergens (with appropriate considerations; specialist practice). | Some food allergens, drugs and pollens not available for testing. |
In most cases have better sensitivity for clinically relevant allergies. | Reasonably good sensitivity. |
Fresh food allergens (prick-to-prick) available with good sensitivity. | Fresh allergens not available. |
No interference from high total IgE. | False positives possible with high total IgE levels. |
Numerical measurements may vary by different operators. | Numerical results obtained on different types of equipment are not directly comparable. |